In the face of public health emergencies, medical libraries provide various types of intelligent knowledge services for relevant users based on the available resources and conditions, and take active actions, which is of great significance for medical libraries to fulfill their original mission and responsibilities with practical actions, expand their business scope and innovate service forms. The intelligent service of medical library for public health emergencies is a typical complex system engineering, which requires the cooperation of staff with different professional knowledge and skills. According to a series of systematic processes, intelligent service uses various types of hardware and software resources to realize intelligent knowledge service and decision support. Based on the WSR system methodology in the field of systems engineering, this paper constructs a medical library’s intelligent service model for public health emergencies. The model is a three-dimensional space structure composed of the physical (Wu in Chinese) dimension (W), the common sense (Shi in Chinese) dimension (S), and the human (Ren in Chinese) dimension (R). The article analyzes and discusses the functions and implementation paths of each dimension in detail.